FRANKFURT -- The CEO of Deutsche Bank reassured employees and markets that the company's finances were "rock-solid" as Europe's banks took another a beating in the stock market Tuesday.

Shares in Germany's biggest lender were down another 5 per cent in afternoon trading in Europe. They're now down 23 per cent since Jan. 28, the day bank reported a 6.8 billion euro ($7.5 billion) loss for 2015.

CEO John Cryan told employees in a message posted on the company's website that they can tell clients the bank's capital reserves and risk profile make it "rock-solid."

The bank's sagging shares reflect converging factors that are undermining bank shares across in Europe. Competitor Credit Suisse last week announced a loss of 5.83 billion Swiss francs ($5.8 billion) for last year, while four failing Italian banks needed to be bailed out in November. Banks in the 19 countries that use the euro have some 1.9 trillion euros in loans that aren't being paid back on time.

More broadly, falling share markets worldwide have made investors take a second look at the risk levels of their holdings.

Shares in Credit Suisse were off 6.9 per cent Tuesday, UniCredit 6.5 per cent, Royal Bank of Scotland, 3 per cent, Switzerland's UBS 5.1 per cent.

More narrowly, markets have focused recently on complex financial instruments issued by banks dubbed contingent convertible bonds. Deutsche Bank has some 350 million euros in payments on some due by April 30, and had to issue a statement Monday evening after markets closed assuring it had the money to pay.

Ironically, the instruments have been encouraged by regulators seeking to protect taxpayers from the risk of having to bail out banks. The bonds in theory help avoid that risk since they can be written down or converted to shares if the banks' capital reserves dwindle. So far, no bank has defaulted. But the bonds contain provisions that mean banks can skip interest payments without being declared in default.

"Investors are concerned that banks which are under stress might miss coupon payments to bondholders," wrote analyst Neil MacKinnon at VTB Capital.